JP2812966B2 - Liquid jet recording head - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a liquid jet recording head, and more particularly, to a heating element substrate of a recording head of a thermal ink jet printer.

2. Description of the Related Art Non-impact recording methods have recently attracted attention in that the generation of noise during recording is extremely small to a negligible level. Among them, the so-called ink jet recording method, which can perform high-speed recording and can perform recording on so-called plain paper without requiring a special fixing process, is an extremely powerful recording method. Some have been proposed and commercialized with improvements, while others are still being put to practical use.

In such an ink jet recording method, recording is performed by flying droplets of a recording liquid called so-called ink and attaching the droplets to a recording member. The control method for controlling the flying direction of the generated recording liquid droplet is roughly classified into several types.

First, the first method is disclosed in, for example, US Pat. No. 3,060,429 (Tele type method),
Recording liquid droplets are generated by electrostatic attraction, and the generated recording liquid droplets are subjected to electric field control according to a recording signal, and recording is performed by selectively adhering the recording liquid droplets onto a recording member. It is.

More specifically, in more detail, an electric field is applied between the nozzle and the accelerating electrode to discharge a uniformly charged droplet of the recording liquid from the nozzle, and the discharged droplet of the recording liquid is converted into a recording signal. In accordance with this, recording is performed by causing the droplets to fly between the xy deflection electrodes configured so as to be electrically controllable and selectively adhering small droplets onto the recording member by a change in the intensity of the electric field.

The second method is described, for example, in US Pat. No. 3,596,275,
The method disclosed in US Pat. No. 3,298,030 and the like (S
Weet method) in which droplets of the recording liquid with a controlled charge amount are generated by a continuous vibration generation method, and the generated droplets with a controlled charge amount are subjected to a uniform electric field. The recording is performed on the recording member by flying between the deflection electrodes.

More specifically, a charging electrode configured so that a recording signal is applied in front of an orifice (ejection port) of a nozzle, which is a part of a recording head provided with a piezoelectric vibrating element, is separated by a predetermined distance. The piezoelectric vibrating element is mechanically vibrated by applying an electric signal of a constant frequency to the piezoelectric vibrating element, and a droplet of the recording liquid is discharged from the discharge port. At this time, a charge is electrostatically induced in the recording liquid droplet discharged by the charging electrode, and the droplet is charged with a charge amount according to the recording signal. When the droplet of the recording liquid whose charge amount is controlled flies between the deflection electrodes to which a constant electric field is uniformly applied, the droplet is deflected according to the added charge amount and carries a recording signal. Only the recording material can be deposited on the recording member.

The third method is a method (Hertz method) disclosed in, for example, US Pat. No. 3,416,153, in which an electric field is applied between a nozzle and a ring-shaped charging electrode, and a continuous vibration generation method is used. This is a method in which small droplets are generated and atomized for recording. That is, in this method, the atomization state of the small droplet is controlled by modulating the electric field intensity applied between the nozzle and the charging electrode in accordance with the recording signal, and the image is recorded with the gradation of the recorded image.

The fourth system is, for example, a system (Stemme system) disclosed in US Pat. No. 3,747,120, and this system is fundamentally different from the above three systems in principle.

That is, in each of the three methods, the droplet of the recording liquid discharged from the nozzle is electrically controlled during the flight, and the droplet carrying the recording signal is selectively attached to the recording member. On the other hand, according to the Stemme method, recording is performed by ejecting a small droplet of recording liquid from an ejection port in accordance with a recording signal.

That is, in the Stemme method, the piezoelectric vibrating element attached to the recording head having the ejection port for ejecting the recording liquid includes:
Applying an electrical recording signal, converting the electrical recording signal into mechanical vibration of a piezo-vibrating element, and ejecting a droplet of the recording liquid from the ejection port in accordance with the mechanical vibration to cause the droplet to fly and adhere to the recording member. Is to record.

Each of these four conventional methods has its own features, but on the other hand, there are points that can be solved.

That is, in the first to third methods, the direct energy of the generation of the droplet of the recording liquid is electric energy,
Droplet deflection control is also electric field control. Therefore, the first method is simple in structure, but requires a high voltage to generate small droplets, and is not suitable for high-speed printing because it is difficult to use a multi-nozzle recording head.

The second method enables multi-nozzle recording heads and is suitable for high-speed recording. However, the method is complicated in structure, and the electrical control of small droplets of recording liquid is difficult and difficult. Are liable to occur.

The third method has a feature that an image having excellent gradation can be recorded by atomizing a recording liquid droplet, but on the other hand, it is difficult to control the atomization state, and fogging occurs in the recorded image. In addition, there are problems such as the fact that it is difficult to use a multi-nozzle recording head, and it is not suitable for high-speed recording.

The fourth scheme has relatively many advantages over the first to third schemes. That is, in order to perform recording by discharging the recording liquid from the discharge port of the nozzle on demand (on-demand), it is simple in terms of the configuration. It is not necessary to collect small droplets that are not required for recording an image, and there is no need to use a conductive recording liquid as in the first and second methods, and the recording liquid material Has a great advantage such as a large degree of freedom. However, on the other hand, it is difficult to form a multi-nozzle recording head because there are problems in processing the recording head and it is extremely difficult to reduce the size of the piezoelectric vibrating element having a desired resonance number. However, since the recording liquid droplets are ejected and fly by the mechanical energy of mechanical vibration of the piezo-vibration element, it is not suitable for high-speed recording.

Further, Japanese Patent Application Laid-Open No. 48-9622 (the aforementioned U.S. Pat.
No. 120) describes, as a modification, the use of thermal energy instead of the mechanical vibration energy by means such as the piezo-vibration element.

That is, the above-mentioned publication describes a so-called bubble jet liquid jet recording apparatus which uses a heating coil for directly heating a liquid as a pressure increasing means instead of a piezo vibrating element in order to generate vapor which causes a pressure increase. I have.

However, the above publication discloses that a heating coil serving as a pressure increasing means is energized to directly evaporate the liquid ink in a bag-shaped ink chamber (liquid chamber) having only one opening through which the liquid ink can enter and exit. However, there is no suggestion as to how to heat the liquid when the liquid is continuously and repeatedly discharged. In addition, since the position where the heating coil is provided is provided at the deepest part of the bag-shaped liquid chamber far from the supply path of the liquid ink, in addition to being complicated in terms of the head structure, continuous It is not suitable for repeated use.

Moreover, according to the technical contents described in the above-mentioned publication, it is not possible to quickly form a preparation state for the next liquid discharge after performing the liquid discharge with the generated heat which is practically important.

As described above, the conventional method has advantages and disadvantages in terms of configuration, high-speed recording, multi-nozzle recording head, generation of satellite dots and occurrence of fogging of a recorded image, etc. There was a restriction that only the application was possible.

In addition, the "bubble jet recording element" (Makoto Shibata, Akira Asai, 1987 National Meeting of the Institute of Electrical Engineers of Japan, S.7-35 to S.7-38) has a description of the heater board process. The formation of SiO ₂ ) is disclosed. This SiO ₂ film works as a heat storage layer. JP
Japanese Patent Application Laid-Open No. 60-159060 discloses a technique in which a protective layer is continuously formed in a strip shape on a heating resistor layer. Tokiko 63-26708
And JP-A-60-116454 disclose a technique for protecting an electrode with an organic material. JP-A-55-132252
Japanese Patent Application Laid-Open Publication No. H11-139,086 discloses a head structure provided with an insulating layer.

The above prior arts are all related to various layers formed on a heating element substrate of a thermal head, and are formed in a plane in a certain area. In a thermal ink jet, as is well known, a heating element provided on a substrate is energized or generates heat in accordance with image information. There are problems such as peeling and cracking due to deformation or thermal distortion of each layer. However, the above prior art does not describe a method for dealing with them. Japanese Patent Publication No. Sho 63-26708 discloses that it is preferable that an organic material protective layer is not provided in a heat generating part in consideration of heat resistance. However, there is a description that it is preferable that an organic material protective film is not provided in the heat generating portion from the viewpoint of heat conductivity, but the problem of thermal distortion is not mentioned.

An object of the present invention is to solve the problem of distortion caused by heat and to improve the durability of a heating element substrate (hence, a head). Notch in the protective layer pattern on the body substrate, which is particularly suitable for high-density arrangement (16 lines / mm or more) that could not be achieved by the conventional method in which electrodes were replaced one by one, and can be easily applied. It is intended to provide a liquid jet recording head.

Configuration In order to achieve the above object, the present invention provides a thermal energy acting section that accommodates a recording liquid to be introduced, generates bubbles in the recording liquid by heat, and generates an action force associated with an increase in the volume of the bubbles. A flow path provided with an orifice for communicating with the flow path to discharge the recording liquid as droplets by the action force, and for introducing the recording liquid into the flow path by connecting to the flow path. In a liquid jet recording head comprising: a liquid chamber, and an introduction means for introducing the recording liquid into the liquid chamber, (1) a plurality of thermal energy action sections on one substrate, A heat storage layer formed in a plurality of regions of the heat energy action portion, wherein the heat storage layer has a partially different thickness in a region without the heat energy action portion, or has a partially patterned Missing Or (2) 1
A plurality of thermal energy action portions on a single substrate, the substrate having a heating element protection layer formed in a region extending over a plurality of the heat energy action portions, wherein the heating element protection layer is A region having no heat energy acting portion, a region having a partially different thickness, or a region having a partially missing pattern, or (3) a plurality of heat energy acting portions and The substrate has a plurality of electrodes corresponding to the plurality of thermal energy action portions and connected thereto, and the substrate has an electrode protection layer formed in a region extending over a plurality of the electrodes. Has a region where the thickness is partially different in a region where the thermal energy application section is not provided, or a region where a pattern is partially missing,
Alternatively, (4) a liquid jet recording head having a plurality of thermal energy action sections on a single substrate and a plurality of electrodes corresponding to the plurality of thermal energy action sections and connected thereto. The electrode is formed by laminating a first electrode and a second electrode on the substrate with an insulating layer interposed therebetween, and the insulating layer is formed in the heat energy action section and / or in a region extending over a plurality of the electrodes. A region in which the thermal energy application section and the electrode are not provided, wherein the region has a partially different thickness or a region in which a pattern is partially omitted.

First, the principle of ink ejection by a bubble jet will be described with reference to FIG. In the figure, 21 is a lid substrate, 22
Is a heating element substrate, 27 is a selection (independent) electrode, 28 is a common electrode,
29 is a heating element, 30 is ink, 31 is a bubble, and 32 is a flying ink droplet.

(A) is a steady state, in which the surface tension of the ink 30 and the external pressure are in an equilibrium state at the orifice surface.

3B shows a state in which the heater 29 is heated until the surface temperature of the heater 29 sharply rises and boiling development occurs in the adjacent ink layer, and minute bubbles 31 are scattered.

(C) shows a state in which the adjacent ink layer, which is rapidly heated on the entire surface of the heater 29, is instantaneously vaporized to form a boiling film, and the bubbles 31 grow. At this time, the pressure in the nozzle rises by an amount corresponding to the growth of the bubble, the balance with the external pressure on the orifice surface is lost, and the ink column starts to grow from the orifice.

(D) is a state in which the bubble has grown to the maximum, and the ink 30 corresponding to the volume of the bubble is pushed out from the orifice surface. At this time, no current is flowing through the heater 29, and the surface temperature of the heater 29 is decreasing. The maximum value of the volume of the bubble 31 is slightly delayed from the timing of applying the electric pulse.

(E) shows a state where the bubble 31 is cooled by ink or the like and starts to contract. At the front end of the ink column, the ink column moves forward while maintaining the extruded speed, and at the rear end, the ink flows backward from the orifice surface into the nozzle due to the decrease in the internal pressure of the nozzle due to the contraction of the bubble, and the ink column is constricted. .

(F) is a state in which the bubble 31 further contracts, the ink comes into contact with the heater surface, and the heater surface is cooled more rapidly. At the orifice surface, the external pressure is higher than the internal pressure of the nozzle, so that the meniscus largely enters the nozzle.
The tip of the ink column is 5-10 m /
Flying at the speed of sec.

In (g), in the process in which the ink is supplied (refilled) to the orifice again by capillary action and returns to the state of (a), the bubbles have completely disappeared.

FIG. 3 is a perspective view of a recording head, FIG. 4 is an exploded perspective view of a lid substrate (a) and a heating element substrate (b) constituting the recording head,
FIG. 5 is a perspective view of the lid substrate viewed from the back side. In the figure, 23 is a recording liquid inlet, 24 is an orifice, 25 is a flow path, and 26 is a region for forming a liquid chamber.

Next, a conventional method for manufacturing a heating element substrate will be described with reference to FIG. FIG. 7 is a cross-sectional view of the heat generating portion. (A) A silicon wafer is thermally oxidized and SiO ₂
(B) HfB ₂ resistor and AI are laminated on the substrate 22 on which the (cover heat layer) 10 is formed, and a heating element 29 and electrodes 27 and 28 are formed by photolithography technology. (C) Next, as an insulating layer and an anti-cavitation layer, SiO ₂ and Ta are sequentially laminated on a portion of the AI electrode except for a wire bonding portion, and then only Ta is stripped around the heating element by photolithography technology. Perform patterning. Then, the resin layer (protective layer) 11 is patterned on the SiO ₂ layer not covered with Ta to complete the heating element substrate. The purpose of this resin layer 11 is to enhance the isolation between the ink and the electrodes, and is not laminated on the heating element.

The above description is a conventional example. For example, an alumina substrate with a glaze layer often used in a technique such as a thermal head can be used as a substrate material. Both the SiO ₂ film on the silicon substrate and the glaze layer (the composition is the same as glass) on the alumina substrate work as a heat storage layer.
The SiO ₂ film is formed by CVD or by a technique such as sputtering in addition to thermal oxidation. The present invention has been made in view of the conventional problem that the durability of a recording head is low due to deformation, peeling from a substrate, or occurrence of cracks due to heat distortion of the heat storage layer. Normally, as shown in FIG. 6A, the heat storage layer is formed on the entire surface of the substrate. However, in such a configuration, the heat generated by the heating element causes heat to be generated locally or the entire heating element substrate.
Due to the difference in the coefficient of thermal expansion between the substrate and the heat storage layer, thermal distortion occurs as described above, causing a problem. Hereinafter, a description will be given based on examples of the present invention.

FIG. 1 is a view for explaining a manufacturing process of an embodiment of a recording head according to the present invention. As a relief structure for relaxing thermal strain in at least one place in a heat storage layer, a slit-shaped pattern (a circle may be used). ) Alternatively, a cut-out pattern is provided at the end.
(A) is a diagram showing a Si substrate, (d) is a cross-sectional view taken along the line AA of (a), (b) is a diagram in which a heat storage layer (SiO ₂ ) 10 is formed on the Si substrate, and (e) is (b) ) Is a cross-sectional view taken along line BB, (c) is a diagram in which a pattern as a relief structure is formed in the heat storage layer, and (f) is a cross-sectional view taken along line CC in (c). The method of forming a pattern as shown in FIG. 1C is formed by a photolithographic technique and an etching technique, but the description of the method is omitted here. Further, FIG. 1 shows a structure in which both the slit pattern and the notch pattern penetrate to the lower substrate (Si) and Si is exposed in the pattern portion. If it is not convenient if Si is exposed in the process, when etching the SiO ₂ , it may be stopped in the middle and a step of the pattern as shown in FIG. 8 may be used. Alternatively, as shown in FIG. 9, after etching once to the bottom, a thinner SiO ₂ may be formed (the above corresponds to claim 1).

 Next, the heating resistor will be described.

As the useful material constituting the heating resistor, for example, a mixture of tantalum -SiO _2, tantalum nitride, nichrome, silver - palladium alloy, silicon semiconductor or hafnium, lanthanum, zirconium, titanium, tantalum, tungsten, molybdenum , Niobium, chromium, vanadium and the like.

Among these materials constituting the heating resistor, metal borides can be mentioned as being particularly excellent. Among them, hafnium boride has the most excellent properties, and then zirconium boride , Lanthanum boride, tantalum boride, vanadium boride, niobium boride in that order.

The heating resistor can be formed using the above-mentioned materials by a technique such as electron beam evaporation or sputtering. The film thickness of the heating resistor is determined according to its area, material, shape and size of the heat acting portion, and furthermore, actual power consumption, etc., so that the amount of heat generated per unit time is as desired. Is usually 0.001 to 5 μm,
Preferably it is 0.01 to 1 μm.

Next, the heating element protective layer of the present invention will be described. The property required for the protective layer is to protect the heating resistor from the recording liquid without preventing the heat generated by the heating resistor from being effectively transmitted to the recording liquid. Useful materials for forming the protective layer include silicon nitride, magnesium oxide, aluminum oxide, tantalum oxide, zirconium oxide and the like in addition to the above-mentioned SiO ₂ and Ta, and these include electron beam evaporation and sputtering. It can be formed by using the method described above. The thickness of the protective layer is usually 0.01
1010 μm, preferably 0.1-5 μm, optimally 0.1-3 μm
It is desirable that

In FIG. 10, reference numerals 29a and 29b denote heating resistance layers, and reference numerals 13 and 14 denote first and second (heating element) protective layers, respectively. Is formed. FIG. 11 shows a case where the present invention is applied to the second protective layer 14 in FIG. Although only the second protective layer shown in FIG. 10 is written in this example, in the present invention, a notch is formed in the protective layer pattern to reduce thermal distortion. FIG. 12 shows still another embodiment. In this case, a slit-shaped opening is provided. Needless to say, the slit-like opening or notch pattern of the present invention is provided at a position where the heating element is removed. No.
The embodiment shown in FIGS. 11 and 12 is an example in which a notch pattern or a slit-shaped opening pattern is omitted from the pattern of the protective layer. FIGS. 8 and 9 show examples of application to the heat storage layer. As described in the above, the pattern may be such that the pattern does not completely fall to the bottom and stops on the way. Such examples are shown in FIGS. 13 (a) and (b). Fig. 13 (b)
FIG. 4A is a cross-sectional view taken along line DD in FIG. 3A. In such a case, since the pattern is a half-blanked pattern, the position of the pattern may coincide with the underlying heating element. Note that a pattern that is completely drawn down or stops in the middle as shown in FIGS. 11 to 13 is easily formed by photolithography and etching techniques, and the technique is already widely known. The description is omitted. Also, here, the tenth
Although the description has been made with reference to the second protective layer 14 shown in FIG.
The present invention is applied to FIG. In short, the heating element protective layer is deformed by thermal strain, and in order to prevent pattern peeling or cracking, a relief structure for relaxing thermal strain, a notch pattern or a slit pattern opening is provided. (The above is a description of claim 2)
Corresponding to).

 Next, the electrode of the present invention will be described.

As the material constituting the electrode, many of the commonly used electrode materials are effectively used, and specifically, for example, Al, Ag, Au, Pt, Cu, etc. are used. It is provided at a predetermined position in a predetermined size, shape and thickness by a technique such as vapor deposition.

In the present invention, an electrode protection layer is further provided to protect the above-mentioned electrode from ink. Hereinafter, the protective layer (coating) will be described.

In the present invention, as a material for forming a film on the lead electrode, a good film-forming property, a dense structure and few pinholes, expansion for the ink used,
It is desirable to have physical properties such as not dissolving, good adhesion to the lower layer such as an electrode layer, and in some cases, high heat resistance (in consideration of being provided near the heat generating portion of the heat generating element). For example, silicone resin, fluorine resin, aromatic polyamide, addition polymerization type polyimide, polybenzimidazole, metal chelate polymer, titanate, epoxy resin, phthalic acid resin, thermosetting phenol resin, P-vinylphenol resin, Xyloc resin,
Resins such as triazine resin and BT resin (triazine resin and bismaleimide addition polymerization resin) are used. In order to form a film of such a resin, the resin may be diluted with a solvent, applied on a lead electrode using a method such as spin coating, spray coating, or dip coating, and then dried and cured.

In addition, a method of forming a polyxylylene resin and its derivative by vapor deposition is also desirable.

In addition, various organic compound monomers such as thiourea, thioacetamide, vinylfurocene, 1,3,5-trichlorobenzene, chlorobenzene, styrene, ferrocene, picoline, naphthalene, pentymetalbenzene, nitrotoluene, acrylonitrile, diphenylselenide, P-toluidine , P-xylene, N, N-dimethyl-
P-toluidine, toluene, aniline, diphenylmercury, hexamethylbenzene, malononitrile, tetracyanoethylene, thiophene, benzeneselenol, tetrafluoroethylene, ethylene, N-nitrosodiphenylamine, acetylene, 1,2,4, -trichlorobenzene, Propane may be formed on the lead electrode by a plasma polymerization method.

The thickness of the above coating is usually 0.01 μm as the thickness after drying.
1010 μm, preferably 0.1 μm-5 μm, optimally 0.1 μm
３3 μm is preferred.

However, if a high-density multi-orifice type recording head is to be produced, it is desirable to use an organic material which makes microphotolithography extremely easy besides the above-mentioned organic material. Specific examples of such organic materials include, for example, polyimide isoindoloquinazolinedione (trade name: PIQ, manufactured by Hitachi Chemical), polyimide resin (trade name: PYRALIN, manufactured by Dupont), cyclized polybutadiene (trade name) : JSR-CBR, CBR-M
901. Nippon Synthetic Rubber), Photo Nice (trade name: manufactured by Toray), and other photosensitive polyimide resins are preferred.

In the present invention, in order to prevent the electrode protection layer formed using the above-mentioned materials from being deformed and peeled off by the thermal strain and to prevent the occurrence of cracks, Japanese Patent Publication No. 63-26708 and Japanese Unexamined Patent Publication No.
Needless to say, the protective layer is not provided on the heat generating portion as described in JP-A-116454, and furthermore, because it is not enough, the electrode is used as a relief structure for further reducing thermal distortion. A slit-like opening or a notch-like opening pattern is provided at a position where no electrode pattern is provided under the protective layer.

FIG. 14 shows a conventional example of a heating element substrate having an electrode protection layer. In the figure, a hatched portion is an electrode protection layer formed using the above material. Note that, in this example, since the common electrode portion does not come into contact with the ink, no electrode protection layer is provided. In contrast, in the present invention, as shown in FIG. 15 and FIG.
In order to reduce thermal distortion, a slit-like opening or a notch-like opening pattern is provided. This pattern is completely drawn down. Therefore,
These patterns are provided at positions where the lower electrode pattern is removed. FIG. 17 and FIG. 18 show patterns formed for the same purpose, but not completely drawn down. This can be seen from the cross-sectional view taken along the line EE in FIG. Also in this case, it is effective for relaxation of thermal distortion.
In the case of this half-missing pattern, it is not always necessary to avoid the lower electrode pattern (this corresponds to claim 3).

Next, a recording head having a heating element substrate having a laminated structure of electrodes as shown in FIG. 19 and having an insulating layer therebetween will be described. The details of the recording head having such a structure have already been filed by the present applicant (Japanese Patent Application No. 62-2749).
No. 10, Japanese Patent Application No. 63-87963). It should be noted that the material of each layer shown in FIG. 19 is an example, and it goes without saying that the materials described in the other embodiments described above are applied. In the present invention, a slit-shaped opening or a cut-out pattern is provided in the insulating layer of FIG. 19 as a relief structure for relaxing thermal distortion without impairing the insulating property between the upper and lower electrodes or between adjacent electrodes. It is. FIGS. 20 and 21 show examples of slit-like openings and notch-like patterns provided in the insulating layer, respectively. In the present invention, as in the other embodiments described above, the respective patterns are similar to the case where the patterns are drawn down, as in the case of FIGS. 22 (a) and 22 (c). As shown in FIG. 23, the one that is stopped halfway is also effective (the above corresponds to claim 4).

In all the present invention described above, in the drawings for explaining the embodiments, the slit-shaped opening, notch-shaped pattern has been described, but the pattern shape is not limited to them at all, other, As shown in Fig. 24, it can take various shapes, including channels, various types (heating elements, electrodes, etc.).
What is necessary is just to select suitably according to a pattern shape or their positional relationship.

The description of the embodiments according to the present invention has been made by dividing into a heat storage layer, a heating element protection layer, an electrode protection layer, and an insulation layer, respectively.
It is even more effective to combine some or all of those inventions.

Table 1 shows endurance test results obtained by actually applying the present invention and when the present invention is not used as in the conventional case.

The common conditions for the test results shown here are as follows.

・ Orifice size 21μm ・ Continuous excitation frequency fo = 4.2KHz ・ Aqueous ink (pH = 9.8) ・ Substrate material Si ・ Heat storage layer material SiO ₂ (thermal oxide film) ・ Heat element material HfB ₂・ Heat element protection layer SiO ₂ (Sputtering film) ・ Electrode material Al ・ Electrode protection layer Polyimide ・ Flow path material Dupont dry film resist ・ Thermal strain relief pattern shape Slit As is clear from above, the number of times of ejection, that is, continuous durability It can be seen that there is a remarkable effect in terms of performance as compared with those not applying the present invention. In addition, when the sample was examined after the experiment without applying the present invention, cracks were observed in each layer.

Effects As is apparent from the above description, according to the present invention, since the notch is formed in the protective layer pattern of the heating element substrate, the high-density arrangement (which cannot be achieved by the conventional method in which the electrodes are folded one by one) cannot be achieved. 16 / mm or more), and the durability of the recording head is improved by relaxing the thermal distortion.

[Brief description of the drawings]

1 (a) to 1 (f) are views for explaining a manufacturing process of a heat storage layer of a heating element substrate in a liquid jet recording head according to the present invention, and FIGS. Diagram for explaining the principle of bubble generation and disappearance,
FIG. 3 is a perspective view of the recording head, FIG. 4 is an exploded view of the recording head, (a) shows a cover substrate, (b) shows a heating element substrate, and FIG. FIG. 6 is a view for explaining a conventional method of manufacturing a heating element substrate, FIG. 7 is a cross-sectional view of the heating section, and FIG. 8 is a step pattern of a heat storage layer. FIG. 9, FIG. 9 is a view showing a structure of another step pattern of FIG. 8 by another manufacturing method, FIG. 10 is a view for explaining a conventional heating element protection layer, and FIG. 11 is a view showing the present invention. FIG. 12 shows a pattern of a heating element protective layer, FIG.
FIG. 13 is a view showing another protection layer pattern, and FIG. 13 is a view showing a pattern which is not completely removed by another protection layer. FIG. 13 (a) is an overall view, and FIG. 13 (b) is a DD sectional view of FIG. FIG. 14 is a view showing a conventional heating element substrate having an electrode protection layer, FIG. 15 is a view showing a heating element substrate having a slit-like opening pattern according to the present invention, and FIG. 16 is a notch-like opening pattern. FIG. 17 is a diagram showing a heating element substrate having a slit-like half-missing pattern. FIG. 17A is an overall configuration diagram, FIG. 17B is a sectional view taken along line EE of FIG. FIG. 18 is a view showing a heating element substrate having a cut-out half-hollow pattern, FIG. 19 is a view showing a heating element substrate having electrodes having a laminated structure and an insulating layer therebetween, and FIG. FIG. 21 shows an embodiment in which a pattern in which a slit-shaped opening is drawn down is provided. FIG. 21 shows a pattern in which a cutout is drawn down in an insulating layer. FIG. 22 is a view showing another embodiment in which a pattern in which a slit-like opening is not completely drawn down is provided, FIG. 22 (a) is an overall view thereof, and FIG. ) Is a cross-sectional view taken along line FF of (a), FIG. 23 is a view showing another embodiment in which a pattern in which a cutout shape is not completely drawn down is provided, and FIG. 24 is an example of various pattern shapes. FIG. 10 ... heat storage layer, 11 ... electrode protection layer, 12 ... insulating layer, 13 ...
1st heating element protection layer, 14 second heating element protection layer, 21 lid substrate, 22 heating element substrate, 23 recording liquid inlet, 24 orifice, 25 flow path, 27 …… Selective (independent) electrode, 28 ……
Common electrode, 29: Heating element (resistive layer), 30: Ink.

Continuation of front page (56) References JP-A-55-132258 (JP, A) JP-A-60-236758 (JP, A) JP-A-59-194866 (JP, A) JP-A-60-116452 (JP) , A) (58) Field surveyed (Int. Cl. ⁶ , DB name) B41J 2/05

Claims (4)

(57) [Claims] 1. A storage device for accommodating a recording liquid to be introduced,
A flow path provided with a thermal energy action portion for generating air bubbles in the recording liquid by heat and generating an operation force accompanying an increase in the volume of the air bubbles; and Liquid ejection recording comprising an orifice for discharging droplets, a liquid chamber for communicating with the flow path and introducing the recording liquid into the flow path, and an introduction unit for introducing the recording liquid into the liquid chamber. The head has a plurality of thermal energy action parts on one substrate, and the substrate has a heat storage layer formed in a region extending over a plurality of the heat energy action parts, and the heat storage layer is A region where the thickness is partially different in a region where there is no thermal energy action part,
Alternatively, a liquid jet recording head having a region where a pattern is partially removed. 2. A storage device for accommodating a recording liquid to be introduced,
A flow path provided with a thermal energy action portion for generating air bubbles in the recording liquid by heat and generating an operation force accompanying an increase in the volume of the air bubbles; and Liquid ejection recording comprising an orifice for discharging droplets, a liquid chamber for communicating with the flow path and introducing the recording liquid into the flow path, and an introduction unit for introducing the recording liquid into the liquid chamber. The head has a plurality of thermal energy action portions on one substrate, and the substrate has a heating element protection layer formed in a region extending over a plurality of the heat energy action portions. The liquid jet recording head according to claim 1, wherein the layer has a region having a partially different thickness in a region where the thermal energy application section is not provided, or a region in which a pattern is partially removed. 3. A storage device for accommodating a recording liquid to be introduced.
A flow path provided with a thermal energy action portion for generating air bubbles in the recording liquid by heat and generating an operation force accompanying an increase in the volume of the air bubbles; and Liquid ejection recording comprising an orifice for discharging droplets, a liquid chamber for communicating with the flow path and introducing the recording liquid into the flow path, and an introduction unit for introducing the recording liquid into the liquid chamber. The head has a plurality of thermal energy action portions on a single substrate and a plurality of electrodes corresponding to the plurality of thermal energy action portions and connected to the plurality of thermal energy action portions. Electrode protection layer formed in a region extending over the entire region, wherein the electrode protection layer has a region in which there is no heat energy acting portion, a region having a partially different thickness, or a region in which a pattern is partially omitted. To Liquid jet recording head according to symptoms. 4. A container for accommodating a recording liquid to be introduced,
A flow path provided with a thermal energy action portion for generating air bubbles in the recording liquid by heat and generating an operation force accompanying an increase in the volume of the air bubbles; and Liquid ejection recording comprising an orifice for discharging droplets, a liquid chamber for communicating with the flow path and introducing the recording liquid into the flow path, and an introduction unit for introducing the recording liquid into the liquid chamber. In the head, a liquid jet recording head having a plurality of thermal energy action portions and a plurality of electrodes connected to the plurality of thermal energy action portions on one substrate, wherein the electrodes are A first and a second electrode are laminated on the substrate with an insulating layer interposed therebetween, and the insulating layer is formed on the thermal energy acting portion and / or an insulating layer formed in a region extending over a plurality of the electrodes. layer There, in the thermal energy acting portions and no electrode regions, partially different thickness regions,
Alternatively, a liquid jet recording head having a region where a pattern is partially removed.